Methods for deriving a representative biodynamic response of the hand-arm system to vibration.
Dong RG; Welcome DE; McDowell TW; Wu JZ
J Sound Vib 2009 Sep; 325(4-5):1047-1061
Vibration-induced biodynamic responses (BR) of the human hand-arm system measured with subjects participating in an experiment are usually arithmetically averaged and used to represent their mean response. The mean BR data reported from different studies are further arithmetically averaged to form the reference mean response for standardization and other applications. The objectives of this study are to clarify whether such a response-based averaging process could significantly misrepresent the characteristics of the original responses, and to identify an appropriate derivation method. The arithmetically averaged response was directly compared with the response derived from a property-based method proposed in this study. Two sets of reported mechanical impedance data measured at the fingers and the palms of the hands were used to derive the models required for the comparison. This study found that the response-based arithmetic averaging could generate some systematic errors. The range of the subjects' natural frequencies in each resonance mode, the mode damping ratio, and the number of subjects participating in the experiment are among the major factors influencing the level of the errors. An effective and practical approach for reducing the potential for error is to increase the number of subjects in the BR measurement. On the other hand, the property-based derivation method can be generally used to obtain the representative response, but it is less efficient than the response-based derivation method.
Biological-effects; Biological-factors; Biological-monitoring; Cell-biology; Cell-damage; Cell-function; Laboratory-testing; Musculoskeletal-system; Musculoskeletal-system-disorders; Physical-reactions; Risk-analysis; Safety-equipment; Vibration-control; Vibration-effects; Vibration-exposure; Vibration-monitors; Vibration-suppressors; Vibration-effects; Vibration-exposure; Vibration-pickups; Hand-injuries; Hand-tools; Biological-function; Biomechanical-modeling; Biomechanics; Mathematical-models
Ren G. Dong, Health Effects Laboratory Division, Engineering and Control Technology Branch, NIOSH, 1095 Willowdale Road, Morgantown, WV 26505
Journal of Sound and Vibration